ATA5771-PXQW Atmel, ATA5771-PXQW Datasheet - Page 33

• Manufacturer Part Number: ATA5771-PXQW
• Description: XMITTR UHF ASK/FSK 868MHZ 24VQFN
• Manufacturer: Atmel

Specifications of ATA5771-PXQW

• Frequency: 868MHz ~ 928MHz
• Modulation Or Protocol: UHF
• Power - Output: 8dBm
• Voltage - Supply: 2 V ~ 4 V
• Current - Transmitting: 9.8mA
• Data Interface: PCB, Surface Mount
• Memory Size: 4kB Flash, 256B EEPROM, 256B SRAM
• Antenna Connector: PCB, Surface Mount
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 24-VQFN Exposed Pad, 24-HVQFN, 24-SQFN, 24-DHVQFN
• Processor Series: ATA5x
• Core: AVR8
• Data Bus Width: 8 bit
• Program Memory Type: Flash
• Program Memory Size: 4 KB
• Data Ram Size: 256 B
• Interface Type: SPI, USI
• Maximum Clock Frequency: 4 MHz
• Number Of Programmable I/os: 12
• Number Of Timers: 2
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 10 bit, 12 Channel
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Applications: -
• Sensitivity: -
• Data Rate - Maximum: -
• Current - Receiving: -
• Lead Free Status / Rohs Status: Details

4.9.2
4.9.3
4.9.4
9137E–RKE–12/10
Clock Sources
Default Clock Source
Crystal Oscillator
The device has the following clock source options, selectable by Flash Fuse bits as shown
below. The clock from the selected source is input to the Atmel
routed to the appropriate modules.
Table 4-3.
Note:
The various choices for each clocking option is given in the following sections. When the CPU
wakes up from Power-down or Power-save, the selected clock source is used to time the
start-up, ensuring stable Oscillator operation before instruction execution starts. When the
CPU starts from reset, there is an additional delay allowing the power to reach a stable level
before commencing normal operation. The Watchdog Oscillator is used for timing this
real-time part of the start-up time. The number of WDT Oscillator cycles used for each time-out
is shown in
Table 4-4.
The device is shipped with CKSEL = “0010”, SUT = “10”, and CKDIV8 programmed. The
default clock source setting is therefore the Internal RC Oscillator running at 8.0 MHz with lon-
gest start-up time and an initial system clock prescaling of 8, resulting in 1.0 MHz system
clock. This default setting ensures that all users can make their desired clock source setting
using an In-System or High-voltage Programmer.
XTAL1 and XTAL2 are input and output, respectively, of an inverting amplifier which can be
configured for use as an On-chip Oscillator, as shown in
quartz crystal or a ceramic resonator may be used.
C1 and C2 should always be equal for both crystals and resonators. The optimal value of the
capacitors depends on the crystal or resonator in use, the amount of stray capac-itance, and
the electromagnetic noise of the environment. Some initial guidelines for choosing capacitors
for use with crystals are given in
values given by the manufacturer should be used.
Device Clocking Option
External Clock
Calibrated Internal RC Oscillator 8.0 MHz
Watchdog Oscillator 128 kHz
External Low-frequency Oscillator
External Crystal/Ceramic Resonator
Reserved
1. For all fuses “1” means unprogrammed while “0” means programmed.
Table
Typ Time-out
Device Clocking Options Select
Number of Watchdog Oscillator Cycles
4-4.
64 ms
4 ms
Table 4-5 on page
(1)
34. For ceramic resonators, the capacitor
Atmel ATA5771/73/74
Number of Cycles
Figure 4-11 on page
8K (8,192)
®
512
AVR
0101, 0111, 0011,0001
®
clock generator, and
CKSEL3..0
1000-1111
0000
0010
0100
0110
34. Either a
33